Exponential operation device
AssigneeCasio Computer Co., Ltd.
InventorJunichi Yoshida
Life of this patent
Estimating the term…
Abstract
An exponential operation device comprises an exponential operation circuit for carrying out the exponential operation of a term x.sup.y formed of data x and data y; and an operation circuit for judging whether the data x supplied by key depression denotes a positive or negative value, and also whether or not the data y supplied similarly by key depression is an integer. Where the operation circuit judges that the data x denotes a negative value and the data y is an integer, then the exponential operation circuit carries out the exponential operation of the term x.sup.y, thereby providing an answer even when the data x denotes a negative value.
Claims11
An exponential operation device comprising:
- operation means for effecting a calculation on an exponential function represented by data items x and y;
- memory means for temporarily storing a radix data x and exponent data y on which an exponential calculation is to be performed, said memory means being coupled to said operation means for supplying the data x, y to said operation means:
- first judging means coupled to said memory means for judging whether said radix data x stored in said memory means is negative or not and for issuing a corresponding judgement signal;
- second judging means coupled to said memory means for judging whether said exponent data y stored in said memory means is an integer or not and for issuing a corresponding judgement signal;
- and
- control means coupled to said first judging means, to said second judging means and to said operation means for designating the execution of an exponential calculation, x.sup.y, with respect to said operation means on the basis of judgement signals from said first and second judging means.
An exponential operation device comprising:
- operation means for effecting a calculation on an exponential function represented by x.sup.1/y ;
- memory means for temporarily storing radix data x and a reciprocal of an exponent on which an exponential calculation is to be performed, said memory means being coupled to said operation means for supplying the data x and data y to said operation means;
- first judging means coupled to said memory means for judging whether the radix data x stored in said memory means is negative or not and for issuing a corresponding judgement signal;
- second judging means coupled to said memory means for judging whether the data y stored in said memory means is an integer or not and if the data y is an integer, for judging whether the data y which is an integer is an odd number or an even number, and for issuing judgement signals as a result of said judging;
- and
- control means coupled to said first judging means, to said second judging means and to said operation means for designating the execution of an exponential calculation, x.sup.1/y, with respect to said operation means on the basis of judgement signals from the first and second judging means.
The exponential operation device of claim 12, in which said first and second judging means include a full adder for judging whether the data is positive or negative, an integer or not and an even number or not.
Dependencies are inferred from the claim text.